Vitamin D

 Vitamin D

Vitamin D is called sunshine vitamin.

Vitamin D is steroid and it act like hormone.

Vitamin D naturally present;

a. Ultraviolet ray from sunlight

Strike to skin and trigger vitamin D synthesis.

b. In foods

c. Dietary supplements

e. Added to other

Vitamin D form

1. Vitamin D2 (food in plant)

2. Vitamin D3 (food in animal;fish liver)

Sources

Egg, butter, milk

Sunshine exposure

Fat, liver, oil, fatty fish

Fortified food

Absorption

Absorbed presence of bile and fat through lymph and store in liver.

Formation;

7 dihydrocholesterol (present in epidermis skin)

Cholecalciferol (vitamin D3) provitamines

Calcidiol

Calcitriol; active form of Vitamin D.

Function

1. Promotes absorption of calcium and phosphorus from small intestine.

Maintaining serum calcium and phosphorus level.

2. Promotes reabsorption of bone and mobilization of calcium from bones.

3. Vitamin D increase absorption of phosphate by kidney.

4. Cause mineralization of bone

5. Immune regulatory role

6. Vitamin D useful for absorption calcium from gut.

Recommended daily allowance (RDA)

 Infant/Children/ Pregnant/ Nursing women; 400 I.U of vitamin D.

Older children and adult; 200 I.U of vitamin D.

Causes of Vitamin D deficiency

1. Children age

2. Lack of sun exposure

3. Inadequate dietary of vitamin D

Pathophysiology

Vitamin D; useful absorption calcium from gut

Exposure to UV light to epidermis skin, skin cell convert vitamin D from inactive form to active form.

In absence of vitamin D

Dietary calcium can't properly absorbed resulting hypocalcemia.

Leads skeletal abnormality and neuromuscular symptoms.